Most electronic devices that are portable user devices, such as cellular telephones, tablets, and music players, and some non-user devices, such as stationary sensors and monitors, rely upon a rechargeable battery as a primary power source. When one of these electronic devices with a fully charged battery is used to perform a set of operations that are repeated with good predictability, the duration for which the set of operations can be performed until the rechargeable battery is fully discharged, will be slowly decreased due to aging of the battery. For portable user devices, this can lead to user disappointment in the performance of the electronic device. For non-user devices, this can lead to other problems. For example, an electronic sensor that is recharged daily by sunlight may initially provide satisfactory service, such as making three reports per day, but may become unable to do so, due to reduced fully charged battery capacity caused by aging of the battery.
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